Electric ophthalmoscope.



R. h` WAPPLER.

ELECTRIC OPHYHA'LMOSCOPE.

APPLICATloN FxLED JULY 3. 1914.

Patented' Dea 12, 19H5.

BEINBIGLD H. WAPPLEB, OF NEW YORK, N. Y.

ELECTEIIC OPHTHALMOSCOPE.

Specllleaton of Letters Patent.

l"atentost lloc. 123, i936.

.tpplication filed Snly 3, 193.4. Serial No. 848,785.

To ZZ '1 o hom t may concern:

lle it known that l, Remi-101.1) l-l. Pneu, a citizen of the United States of linerica1 residing in borough of il-l'anhattan, city, county, and State of New York, have invented certain new and useful Improvements in Electric Ophthalmoscopes, of which the following is a specification.

This invention relates to 'electric opthalmoseopcs, and aims to provide certain improvements therein.

`llleelnic opthahnoscopes, as heretofore constructed, have had certain' disadvantages which have seriously interfered with their successful use. Such instruments usually)7 comprise a lmndle which may include a suitaille` battery. a small electric lamp housed in the tube in line with the handle, and a inirraz-f' ,set at an angle ofto the axis of the handle and designed to reliect the rays ot light 'l'rom the lamp at a substantially 90 angle. Mounted back of the light tube and mirror are the usual series of lenses throlligh which the operator observes the lens and i-nterior of the eye for the purpose of determining' lesions and retractorjT errors. ln instruments oi this construction the mirror is projected a considerable distance. beyond the object-ive lenses, with the result that the eye of the operator cannot approach the eye to be exan'iined a sufliciently close distance to pei-Init a careful and accurate esamination. Furthermore, in the-endeavor to oblain satisfactory results it is not uncommon that the instrument is brought so close to the pupil of the eye as to injure the lens thereof. As the examination is conducted onlj1 by the vision ot' the operator, it will be apparent that onlyI those rays of light which are reflected througl'i the pupil of the patients '.-t' 'e lens and the pupil of the are discernibleto the latter. lt

W .fre-

operator may imaginary tube Whose diameter' is deter mined .bythe three factors just referred to. Obviously the nearer the eye of the-operator can approach that of the patientvthe shorter this tubewill be, and thc'inore enlarged the ,field oi' vision. This is so small with the present instruments that it is usually vnecessarjT to dilate the pupil of the patient by the use of atropin,.or other drugs.

According to the present invention the instrument is so construeted'as to bring the angle ivhich. is

be said that these rajys pass through an' eye of the operator a i lose as possible to that of the patient, and the parte 'are formed so that there are no prejiectng parts to inl4 jure the eye.' By this; means the field of vision of the operatoru greatly enlarged, and the instrument is rendered safe to the hands of the inexperienced practitioner. It is not necessary in ordinary cases to dilate the pupil of the patient-so that immediate examinations can be made without lengthy preparation.

The principal feature of improvementby which these results are attained is the provision of a. prism mounted abou-fc the electric larnp, Whici prism4 is provided with a refleeting surface preferably formed directly upon the prism, and preilierablji/ having), an angle to the vertical of the prism off about 10. rlhe front face of the prima preferably has an angle of about '35" troni the iertical. These angles mayY he departed .-lozn7 but in any event the prism termed that thebeam of light is bent by the rront face of the prism backwarrll onto the leliecting surface, and thence outwardly through the front fact of the prism at an tical adiis of the instrument.

The invention includes other improvements which will be hereinafter more fully described. p

Referring-to the drawings which illustrate the preferred ,torni of the invention, Figiue 1 is a front elevation of the apparatus. showing it equipped with a. handle and flexible cord Jfor connection with a battery at a distance. Fig. is a vertical section taken on the line 2-2 in Fig. 1. Fig, 3 is a diagrammatic View of the lamp and prism. Fig. 4 is a diagrammatic View in perspective, showing the prism alone.

Referring to the drawings, let E nate leads of any suitable length, adapted to be connected to socket terminals of a suitable source of electricity. The leads pass to a handle F formed of insulating material', and one of the wires, as ll, is connected with a metallic tu-he liE which is electrically connected with one of the terminals of the 'lamp 'G through metallic rod F", the lon-'er portion of which fits removably into the tube as shon'n. to a metallic sleeve F4, on which is 'serrirecl a sleeve F, a portion of which F projects uppnt in a'.

The opposite lea-d Ez'is connected approximately 90 to the verwardly 'l'roin the hiiiidle, und is designed 'to cont-iet with the. suiteli member ll4 (Fig. l). The hitter 'eoii'iprises iiii eiiliirgeiiieiit H torii'ied en the eiid of the slcei'e ll'' which piisses lip'wiirdiy :ind cont-.iets with one ot the terminals ot the lmnp G. 'lhe eiiliirgenient Il is provided with two insulating ,plugs LF :ind ll,l :ind the enlargement und plugs ure'eiieh i'oriiied with :i groove l-l". This groove is, however, eut ziuiiy ut the piirt 'I-l" ofthe plugr l-l, in order that the nrinli" muy pass upu'erdly piist the lower portion di the eiilurgement, so that its pro 'cetinir portion HT muy renali the groove lt ywill be' understood thiit the hundle is sepuriited from .the opthiiliiioscope proper by'reinoi'iil ol" the rod F" :troni the.tube F, und that the uriii l"5 :icts :is :i iiieeliuiiicntde tent to hold the ports together.

The lump li which is of the ordinary incandescent yo/.i hm. .retei;.il.ily mounted above it n eoneentrniing lens "K which is best carried iii ii iiietiillie tube K, :ind above the tube is mounted :i prism L, preferably eiirried by ai tube M which surrounds the lump und other fittings lieieinbetore deseribed.

The'prisiii L isihest seen in the diagram mnt-ie views, Figs. 25 und Ll. The prisni'is enernlly cylindrical in forni, the lower art einig preferably convex :is shown it L so that u further eoneentrution of the beinn of 'to the axis of the prism.

light takes place :it this point. On the front side of the prism it is formed with :i flat face L2 which extends it ,u hsuitable tingle to the axis oit the prisin,tli1it shown upproximating 35". At 'the top and reiir of the prism is also formed .fr lint :talee L4 which preferably extends iit :in :ingle oi' about 10 The reii'r uee L is intended :is ii reflecting ture, Vend to' this end it is either` directly silvered or is provided with u sepziriitelif formed relleeting surface, such :is :i small mirror mounted :it the reur oi it und extendingr ut the saine angle. In Figs. 3 und l is showncliagrain ninticiillythe 'pussiige of u' benin of light 'trom the hun) (zi. The. rays are condensed by the. lens I und further concentrated by the spherical iiice L' ot' the prism. The prism muy be so constructed the benin slightly toward the tliit face L, but in any eye-nt the benin is passed teurwnrdljy' to t'li'e reflecting surface L and bent Slight-'ly by the fiiee L, so lliut us the benin emerges from the prism it follows i1 direction which is substantially 90 to the axis of A the risiii. One eil'eet secured by the prism is't at the net-unl reilecting tace, which throws the beam of light forwardly at Suhstuntiully nu :ingle of 90 from the axis of the benin of light. 'is displaced well to 4the rear of such uxis,so that it does' not project from the instinnieiit. ln addition to this the flut iiee L2 formed ut the iront of us to refriict the prism is iidiniriihly :idiipled l'oi` -ippreaching the pupil o1' the eyeT .-i-i llii'thioperator is :iblc to bringe,r the iii\-.|.iiiiiicl|i iiiiieh closer lo llie eye of the piilieiit lliuii i possible with e.\"istin'( iiisti'uiiitiitsA The usual disks N cui'ryiiigi,r the usuiil series oi' lenses muy he. mounted directly bueh of the prism, :is best shown in Fig. 2, und the eye of the operador is hence iible to :ipproiieli i'ery closely to the reur of the prism. The result o1 this construction is th-.it the imaginary tube. formed by the eye of the oieraitor und the eye of the patient is greutiy shortened, und the instrument hence permits u. niiicli wider icld of` observation thun those now in use. As before stated, it is not necessary to dilate the pupil of the patient,4 since u thorough exzimiiiiiF tion can be niude with the pupil iii its nurA mail or contracted state.

It is quite desirable for certain purposes to vary the quality of the benin which the ii'istrument-projeets, :ind this is doi-ie in the present derive by lengthening the ilistnnce between the prism und the lump G. To this end the tube M is mounted to slide upon the tube H2, und to assist in adjusting it. A thumb-piece hi2 is provided nt the loii'er end of the tube M by means of which the operator ein easily more the prism tube (with the disks N N) to the required position. V

lVliile I linve shown :ind deserilmd one forni of the invention, 'it is understood that I do not irish to be limited thereto, since furious ehunges muy be mede therein with-A out departing from `the spirit ot the iiii'eii tion.

What I cliiiin is:-

1.1n un oplithiilinoscope, the combinav tion of u source ot light,y and a prism through which the light is projected, said prism haring' ii substantially flat surface ut its front extending ut Such annugle to the i'ixis ot the prism-that the ray is totnlly ieieeted :ind ii substantially fliitasurfuce at its reiir also extendingv :it un :ingle to the axis of the prism, :ind it reflecting medium et the lust-named'sin-fuese. Y

2. In un ophthiilnioseo the combination off ii source of' 1i iite, und u. through which thelightzs projected, 'said prism .having u Substantially vdat 'reecting surface at its front extending :it-an angleto the uxis of 'die prism and a 'substuntilly -liit surface at. its reim also extending-at an angle tothe axis of the prism, .siidlsecond fliit surface being coated with a' reflecting medium.

In un oplithiilmoscope, the comliinaticin of a source of light, and a prism through which the light is projected, said fprismlmving fi'substitjitially flat. reflecting surface :it its front extending-at an angle to the axis ofthe prisnifrnd a substantially dat 'surface ing surface and o, substantially flat' rearsurface, both surfaces extendingangularly to the axis of the prism, and the :latter surf acebeing provided with a reflecting rneium.

5. In an ophthalmoscope, a source ofl light and means for deflecting a substantiallyvertical ray of light to a substantially horizontal direction, said means comprising a` reflector for reflecting the vertical ray toward the rear of the ophthalmo'scope and a reflector' in the path of the reflected ray, adapted to reflect said ray forwardly, the two reflectors bein so arranged that the sum of the angles o incidence and reflection of' the vertical ray is considerably greater than the snm of the angles of incidence and reflection of the reflected ray, the ray passA ing through the device without crossing itself.

i (i. In an ophthalmoscope, a. source of light and means for deflecting a siibstantially vert-ical ray of light to a substantially horiV zontal directiomsaid means comprising a reflector for reflecting the vertical ray toward the rear of the oph'thalrnoscope and a reflector in the path of the reflected ray, adapted to reflect said ray forwardly, the two reflectors being so arranged-that the :sum of the angles ofincidence and reflection of the vertical ray is considerably greater than the snm of the angles of incidence and.

reflection of the reflected ray, the ray passing:r through the device wlthont vcrossing it- Self, and a reractor adapted-toi bend the reflected ray to the desired direction.

7. In an ophthalmoscope, a source of liiht ly i and means for deflectin-g ,a substantie vertical ray of light to a substantially hori zontal direction, seid means comprising a piece of light-transmitting substance having a reflecting surface for reflectingthel vertical ray toward the rear of the ophthalmoscope and a reflecting surface in the path of' the reflected ray adapted to .reflect saidv -ray forwardly, the two reflectors being so arranged that the sum of the angles ofincidence and reflection of'the vertical rayis considerably greater than the snm of the angles of incidence and reflection of the rellected ray, the raypassing through the de vice without crossing itself;

8. In an ophtha-lmoscope, a source of light and means f'or deflecting a substantially vertical ray ofllight to a substantially horizon A tal, direction, said means comprising apiece of lightftransmitting substance having a refleeting surface for reflecting the vertical ray toward the rear of the ophthahnoscope and a reflecting surface in the path of the reflected ray adapted to reflect .said 'ray forwardly, the two reflectors being so arranged that the sum of the anglesof incidence and reflection of the vertical ray is considerably greatertlian the sinn of the angles of incidence and reflection of the reflected ray, the ray passing through the device 1.irithont crossingr itself` and: a refr-acting surface adapted to bend the reflected ray to the desired direction.

In witness whereof, I have hereunto signed my naine in the. presence of two sulr scribing witnesses.

REINHOLD H. WAPPLER.

lVitnesses Anrnnn Lrsnnnnn, Il. Man'iiN Knostrnz. 

